1. Field of the Invention
The present invention relates to a liquid crystal panel and alignment film thereof, and more specifically to a liquid crystal display has a modified polyimide alignment film that reduces image sticking.
2. Description of the Prior Art
Liquid crystal displays have been widely used in various electronic products. Please refer to FIG. 1, a liquid crystal panel 10 includes a pair of substrates 11, 12 which are correspondingly arranged, a liquid crystal layer 13 sandwiched between the substrates 11, 12, and two alignment films 14, 15 arranged on the substrates 11, 12 and adjacent to the liquid crystal layer 13.
The liquid crystal displays are normally used to display dynamic and static frames. After a static frame has been shown on a liquid crystal display for an extended period, a residual image or profile would easily stick to the display frame when another frame is displayed. This is because the liquid crystal molecules inside the liquid crystal display need to be driven by a high voltage for a prolonged period in order to display the static frame, thereby leads to an increase in the ion density of the liquid crystal. When the liquid crystal display needs to display the next frame, the driving voltage cannot accurately control the state of alignment of the liquid crystal molecules in this area because the ion density of liquid crystal in part of this area has been changed. Thus, the gray level brightness of the frame in this area of the liquid crystal display will not be the expected one. As a result, the next display frame is likely to have a darker or a brighter image profile.
Therefore, there is a need to provide the liquid crystal panel and alignment film thereof which can improve the problem of image sticking, so as to overcome the disadvantage in the prior art.